Understanding Temporary Table Space Usage

If direct path read temp or direct path write temp are among the top wait events, it may indicate a problem. Check the total wait time for these events. If the wait time for these events is a significant portion of the total wait time, then sorts, hash joins, or group by operations may be spilling to disk.

You will find path read temp and direct path write temp in the Foreground Wait Events table. One or both may be missing from the table. If they are missing, temporary table space usage is unlikely to be a problem.